Centralized traffic controlling system for railroads



June'z, 1936. T. J. JUDGE CENTRALIZED TRAFFIC CONTROLLING SYSTEM FOR RAILROADS Filed Jan. 26, 1933 BY w 1 M ATTORNEY Patented June 2, 1936 UNITED STATES CENTRALIZED TRAFFIC CONTROLLING SYSTEM FUR RAILROADS Thomas J. Judge, Rochester, N. Y., assignor to General Railway Signal Company, Rochester,

Application January 26, 1933, Serial No. 653,679

15 Claims.

invention relates to railway traffic controlling systems, and more particularly to a communicating means in such a system for continuously transmitting a plurality of messages over a single line circuit. This invention is an improvement over the invention disclosed in my prior application Ser. No. 622,649 filed July 15, 1932, and only the improvement over said prior application is claimed herein.

In controlling distant railway traffic controlling devices from a central point, it is expedient to employ a minimum number of line wires extending from the control point to the various distant locations, both because of the cost of the line wire as well as the increased cost of maintenance of a larger number of wires over the considerable distances necessary to extend the line circuits. It is found convenient in such systems to not only provide means for controlling distant devices, such as switches and signals, but to receive indications at the control point of the operated position of the switches and an indication as to the clear or stop indication displayed by the signals, which consequently enables considerable saving to be made by multiplying the number of such indications which'may be transmitted over each indicating circuit.

In view of the above and other considerations, it is proposed in accordance with the present invention to provide a communicating means whereby a continuous indication of the operated position of a track switch and of the indication displayed by the associated signals may be transmitted to a remote point over a single line circuit.

Other objects, purposes and characteristic features of the present invention will become apparent as the description thereof progresses, during which reference will be made to the accompanying drawing, which shows in a diagrammatic and conventional manner a system for indicating at a distant point the operated. position of a track switch and the indication displayed by the associated signals, all in accordance with the present invention. g

A portion of a miniature track diagram MT is diagrammatically shown in the accompanying drawing corresponding to a section of distant actual track T, which track T has directional signals ES, WS and W SA governing traflic movements thereover and an associate-d indicating light SK is provided in the track diagram for indicating whenever any one of these signals displays a clear indication. A track switch TS is included in the track T and is conventionally shown as operated by switch machine SM, and

two indicating lamps NK and RK are provided track switchTS as indicated by the dotted line,

or that is, the polar contacts of this relay are operated either to their left or right extreme positions according to the normal or reverse position of the track switch TS and is de-energized while the position of the switch is being changed,

all of which is accomplished in the well known and conventional manner. The relay M'is normally energized whenever all of the signals ES, WS'and WSA are at stop, but is arranged to be de-energized whenever any one of these signals is cleared, all of which is also well known in the art, and consequently has herein beenv merely indicated by dotted lines.

A source of energy for the line circuit is shown as a split potential battery B, and it is 'understood that the wire L is the line wire connecting the particular section of track T with the control panel MT shown herein, which points may be located a considerable distance from each other,

and alsoit is understood that the wire COM may .be a common line Wire for various other control or indicating circuits in the trafiic controlling system. A local source of energy is required at the location of the track diagram which is not shown herein but the symbols and are used to indicate the opposite terminals of such source. r

The local signaling circuits whichhave herein been omitted but are necessary for the proper operation of the trackswitch and the associated signals are so arranged that it is not possible to operate the track switch TS to a new position whenever any one of the associated signals ES, WS or WSA is displaying a clear indication, and consequently considering that the track switch .TS has been operatedto its normal position as shown, which positions the polar contact of the relay WP to its left hand position, and considering that all the signals are now at stop, which maintains the relay M energized, the relay K is then energized over a circuit from the ter; minal of battery B, wire 4, front contact 5 of relay M, wire 6, polar contact 1, of relay WP in its left hand position, wire 8, neutral front contact 9 of relay WP, line wire L, through the windings of relay K, wire. Ill, common line wire COM, wire II, to the center terminal (0) of the battery B.

This energization of the relay K, with current flowing from right to left through its operating winding (which may be termed for convenience polarity) operates its polar contacts to their extreme left hand positions thereby completing a circuit for picking up the slow-releasing relay NR from polar contact l3 of relay K in its left hand position, wire l4, back contact l5 of relay RR, wires I6 and I1, through the windings of relay NR to With the relay NR thus picked up and relay RR de-energized, an indication of the normal alinement of the track switch TS is given on the miniature track diagram MT by energizing the indicating light NK from back contact I9 of relay RR, wire 20, front contact 2| of relay NR, wires 22 and 23, through the indicating light NK to It will now be considered that, with the track switch TS in its normal position as shown, either signal ES or WS is cleared thereby de-energizing relay M in the manner previously stated. The

,relay M dropping completes a circuit for applying the reverse polarity of energization to the relay K over a circuit from the center terminal (0) of battery B, wire II, common line wire COM, wire l8, through the windings of relay K, line wire L, neutral front contact 9 of relay WP, wire 8, polar contact 1 of relay WP in its left hand position, wire 6, back contact 5 of relay M, wires 25 and 26, to the terminal of battery B.

This reverse polarity of energization of relay K or-namely with current flowing from left to right through its windings (which may be conveniently termed polarity) operates its polar contacts to their extreme right hand positions, but the relay NR having slow-releasing characteristics does not drop during the period in which the polar contacts of relay K are being shifted, and conse- 'quently, a stick circuit for relay NR is now completed from contact l3 of relay K in its right hand position, wire 28, front contact 29 of relay NR, wires 30 and I1, through the windings of relay NR to With the contacts of relay K in their right hand positions and the relay NR picked up, an indication of a clear signal is given 'by energizing the indicating light SK over a circuit from back contact [9 of relay RR, wire 20, front contact 2| of relay NR, wires 22 and 32, contact 33 of relay K in its right hand position, wire 34, through the indicating light SK to An indication of the operated position of the switch TS is maintained also in as much as the relay NR previously energized in accordance with the switch position is still held 7 up to energize the indicating light NK.

The relay WP is arranged, as previously described, to repeat the operated position of the track switch TS and consequently, if the signals are again placed at stop and the switch machine SM is controlled to operate the switch TS from its normal position as shown to its reverse position, the relay WP will be de-energized for an interval of time in which the switch TS is being operated from its normal to its reverse position, all of which is conventional in the control of the WP relay. In this interval of time during which the relay WP is de-energized, its neutral front contact 9 will be open to de-energize the relay K for a sufficient time to effect the dropping of the slow releasing relay NR by opening its energizing circuit at contact l3 of relay K in its center or de-energized position. With both relays NR and RR de-energized, the indicating lights NK and RK will both be extinguished to indicate that the switch TS is in an intermediate or mid-stroke position. However, as soon as the switch TS assumes its reverse position, the relay WP will again be energized with a polarity effective to operate its polar contact to its extreme right hand position thereby completing an energizing circuit for relay K from the central terminal (0) of battery B, wire ll, common line wire COM, wire l8, through the windings of relay K, line wire L, neutral front contact 9 of relay WP, wire 8, polar contact I of relay WP in its right hand position, wire 35, front contact 36 of relay M, wires 31 and 26 to the terminal of battery B. This polarity of energization of relay K operates its polar contacts to their right hand positions thereby completing a circuit for picking up the slow-releasing relay RR from contact |3 of relay K in its right hand position, wire 28, back contact-29 of relay NR, wires 38 and 39, through the windings of relay RR to With the relay RR picked up and the relay NR deenergized, an indication of the reverse alinement of the track switch TS is given at the miniature track diagram MT by energizing the indicating lamp RK over a circuit from back contact 2| of relay NR, wire 20, front contact l9 of relay RR, wires 40 and 4|, through the indicating light RK to Considering now that either signal ES or WSA clears to de-energize the relay M, a circuit is completed for reversing the polarity of energization of relay K from the terminal of battery B, wire 4, back contact 36 of relay M, wire 35, polar contact 1 of relay WP in its right hand position, wire 8, neutral front contact 9 of relay WP, line wire L, through the windings of relay K, wire I0, common line wire COM, wire I I to the center terminal (c) of battery B. This reversal of polarity of the relay K actuates its polar contacts to the left to complete a stick-circuit for the slow-releasing relay RR in the same manner as previously described for relay NR, which stick circuit may be traced from contact l3 of relay K in its left hand position, wire I4, front contact l5 of relay RR, wires 42 and 39, through the windings of relay RR to An indication of a clear signal is now given on the miniature track diagram MT by energizing the indicating lamp SK from ,back contact 2| of relay NR, wire 20, front contact H) of relay RR, wires 40 and 43, contact 33 of relay K in its left hand position, wire 34, through the indicating lamp SK to A communicating means for a railway traffic controlling system has thus been provided which permits an indication of the condition of a track intermediate position. This selected polarity of energization of the line circuit is effective at the remote location to energize either of two slowreleasing relaysaccording to the position of the contacts of a polarized line relay, which slowreleasing relays individually control associated indicators to show the existing condition ofthe track switch.

The present system provides for indicating at the remote location the condition of signals associated with the track switch by quickly changing the polarity of energizationof the same line circuit selected by the position of the switch whenever any one of these signals displays a clear or proceed indication. The selection of the slow-releasing relays at the remote location does not follow this quick shifting of' the polar contacts of the line relay efiected by the clearing of a signal, and the slow-releasing relay previously selected in accordance with the switch position is retained energized by a stick circuit thereby setting up a condition in which the position of the polar contacts of the line relay are out of correspondence with the selection of the slow-releasing relays. A signal indicator is then controlled by a circuit checking the correspondence between the position of the polar line relay contacts and the selection of the slow-releasing relays, and the indicationof the switch position is retained during the signal-ciear'indication inasmuch as the switch indicators are controlled only by the slow-releasing relays.

It will be-obvious that a change in position of the switch will pole-change the energization of the line circuit to indicate the new position, but in doing so the line circuit is de energized for a period of time in which the switch is operating thereby dropping the previously selected slowreleasing relay and allowing the following energizationto'sel'ect the slow-releasing relay corresponding to the position of the polarline relay contacts. Inother words, the present system distinguishes between the pole-changing of the line circuit for transmitting a signal-clear indication and that for transmitting. a change in switch position by the length of the de-energi'zed period during the polarity change.

The above rather specific description of" one form of the present invention is given solely by way of example; andis not intended in any manner whatsoever in a limiting sense. It is also to be understood that various modifications, adaptations and alterations may be applied to meet the requirements of practice, without in any manner departing from the-spirit or scope ofthe present invention, except as limited by the appended claims.

Having thus described my invention, what I claim is:

1. In an indication communicatingsystem, a track diagram, 2. single line circuit extending from said track diagram to-an associated distant track location, a track switch and associated signals at said track location, a polarized line' relay associated with said track diagram, two slow-releasing stick relays associated with said line relay, means including said line relay for selectively energizing either of said slow-releasing stick relays in accordance with the operatedposition of said" track switch, means foroperating said line relay when any of said associated signals displays aclear indication in a manner to close a stick circuit for'maintaining a previously selected slow-releasing stick relayenergized and to effect an indication onsaid-track'diagram, and a switch indicating means on said track diagram controlled inaccordance with the energization of said slow-releasing stick relays.

2. In an indication communicating system, a track diagram, a single line circuit extending from said trackdiagram to an associated distant track location, a track. switchand associatedsignals at said track location, a. polarized line.- relay associated with: said trackdiagram; twoslow-releasing stick relays associated with said: line relay, means. including said line relay for: selectively energizing, either of said. slow rel'easing stick relays in accordance (with operated position of said track switch and; to- .eifect the de-energization of both of said slow-releasing stick relays during: operation of said track switch, means for operating, said line relay when any of said associated signals displays a clear indication in a: manner to: close a stick circuit for maintaining a previousl y selected slows-releasing stick relay energized and to efiect an. in:- dication on said track diagram; and; a; indicating means on said. track diagram controlled in accordance with the energiz'ationof'saidslow releasing stick relays.

3. In, combination, a liner circuit, a source of polarized energy at one end of said line circuit, a polarized relay at the other end of said line circuit, a first contact means arranged for-selecting the. direction of current insaid" linecircuit, a second contact means arranged in series with said first contact means-forselecting the direction of current insaid line circuit, athirdcontact means arranged foropening said line: circuit during actuation of said first contactmeans, two slow-acting stick relays; associated with said polarized relay, means including. said polarized relay for selectively energizing either of said slow-acting stick relays according. to the position of said first contact means, means for:- changing the position of said polarized-ielay and closing a stick circuit for retaining the then energized slow -releasing stick relay energized in accordance with an operation of said second contact means, and means for efiecting' the release of either of said slow-acting stick relays-in: accordance with an operation: of said third contact means.

4. In an indication: communicating. system, a track switch and associated signals, a line circuit extending from said track switch to a distant point, means for energizing said line circuit with a polarity distinctive of the operative position of said track switch and for changing said polarity when one of said signals displays a clear indicas tion, a polar relay'in said line circuit at said distant point, two' slow-acting'relays associatedwith said. polar relay, means for selectively energizing one of said slow-acting relays corresponding to the position of a polar contact ofi said. polar relay and'for retaining the selected slow-acting. relay energized.- when the polar contact of said polar relay is shifted out of correspondence. with; the

selection of said slow-acting relay; and-an indieating means at said distant point controlled in accordance with the selection of said slow-acting relay and in accordance withthe correspondence between said selected relay and the positionof' a polar contactof said polar' relay.

5. In combination, a linecircuit, apolar relay at one endof said line circuit, a three-position and a; two-position circuit. controlling means at the other end of said' line, jcircuit-,, a polarized source of'energy'associatedwith said circuit controlling means, two slow-acting: relays: associated with said polar relay, means to eflect' the energization of one, the other'or neither'of saidrslowacting relays in" response tota first, a second or a third position of said three-position circuit controlling means, and means to: shift the position of said polar relay and retain avpreviously effected energized condition of either slow-releasing relay inresponse to'a quick change in position of said two-position circuit controlling means.

6. In combination; a single line circuit; a polar relay at one end of said linercircuit; two slow acting relays associated with said polar relay; a first relay at the other end of said line circuit arranged to effect the picking up of one, the other or neither of said slow acting relays in correspondence with one energizing polarity, the other energizing polarity or the deenergizing of said polar relayrand a second relay at the other end of said line circuit for efiecting over said line circuit the energization of one of said slow acting relays which is out of correspondence with the energizing polarity of said polar relay.

'7. A system for transmitting and displaying four distinctive indications of trafiic controlling conditions over a single circuit comprising, a single line circuit connecting an ofiice with a distant location, means for continuously energizing said line circuit with current of selected polarities to transmit a first and a second of said indications, means for quickly and slowly shifting the polarity of energization of said line circuit, means responsive to the quick shifting of polarity for transmitting a third and a fourth of said indications, and means for distinctively displaying said indications.

8'. A system for transmitting and displaying fivedistinctive indications of traffic controlling conditions over a single circuit comprising, a single line circuit connecting an ofiice with a distant location, means for continuously energizing said line circuit with current of selected polarities to transmit a first and a second of said indications, means for quickly and slowly shifting the polarity of energization of said line circuit, means responsive to the quick shifting of polarity for transmitting a third and a fourth of said indications, means responsive to the deenergization of said line circuit during said slow shifting for transmitting a fifth of said indications, and means for distinctively displaying said indications.

9. In combination; a line circuit; a polar relay; two slow acting relays at one end of said line circuit; two circuit closing devices at the other end of said line circuit; a source of current associated with said circuit closing devices; means controlled bysaid devices and including said source of ourrent for energizing said line circuit with either polarity and for changing to the oppositepolarity;' means including said polar relay and controlled over said line circuit for effecting the 'energization'of one, the other or neither of said slow acting relays in response to the polarity of energization and the deenergization of said line circuit; and means responsive to the rate of changefrom one to another polarity of energiza- "in" accordance with the positions of said devices,

two slow releasing indicator relays, a pick up circuit for one indicator relay including a normal contact of said polar relay and a back contact of the other indicator relay, a pick up circuit for theother indicator relay including a reverse con tact of said polar relay and a back contact of :said oneindicator relay, a stick circuit for said 'one indicator relay including a reverse contact of said polar relay and a front contact of said one indicator relay, a stick circuit for said other indicator relay including a normal contact of said polar relay and a front contact of said other relay, and indicators for said devices controlled by the 5 contacts of said polar and said slow releasing relays in combination.

11. In a system for indicating various conditions of railway trafiic controlling devices, a track switch and associated signals at a first location, a single line circuit connecting said first location with a second location, fast and slow acting relays, means for energizing said line circuit with selected polarities in accordancewith the normal and reverse positions of said track switch, means responsive to a change in position of said track switch for changing the polarity of energization of said line circuit with a comparatively long deenergization intervening, means responsive to a change in condition of said signals for changing 20 the polarity of energization of said line circuit with a comparatively short de-energization intervening, means including said fast and slow acting relays responsive to the polarity of energization of said line circuit for distinctively indicating at said second location the normal or reverse positions of said track switch, means including said fast and slow acting relays responsive to said long de-energization of said line circuit for indicating at said second location that said track switch is changing its position, and means including said fast and slow acting relays responsive to said short de-energization of said line circuit for indicating at said second location said change in condition of said signals.

12. In a system for indicating various conditions of railway traific controlling devices, a track diagram, a distant track section, a single line circuit extending from said track diagram to said track' section, means at said track section for se- 1, quentially applying a first and a second polarity of energy to said line circuit with either a quick reversal or a comparatively long period of deenergization intervening, means at said track diagram for displaying a first indication in response 5 to the application of energy of one polarity to said line circuit, means at said track diagram for displaying a second indication in response to the application of energy of another polarity to said line circuit with a comparatively long period of de-energization intervening, and means at said track diagram for displaying a third indication in response to the quick reversal of the. polarity of energization of said line circuit.

13. In a system for indicating various conditions of railway trafiic controlling devices; a plurality of indicators at one location; a distant track location; a single line circuit extending between said locations; means at said track location for energizing said line circuit with one polarity under a first condition; means at said track location for de-energizing said line circuit for a predetermined time interval and re-energizing it with the opposite polarity under a second condition; means at said track location for reversing the (1.3 energization of said line circuit with substantially no intervening de-energized period under a third condition; means responsive to said first condition for rendering a first one of said indicators active; means responsive tosaid second condition for rendering a second one of said indicators active; and means responsive to said third condition for rendering a third one of said indicators active.

14. In a signaling system; a first, a second and a third indication lamp; a polar control relay connected to a circuit; means controlled over said circuit for actuating the contacts of said control relay to normal or reverse positions; a first repeating relay and a second repeating relay; means controlled by said control relay in its normal position for completing a pick-up circuit for said first repeating relay; means controlled by said control relay in its reverse position for completing a pick-up circuit for said second repeating relay; means controlled by said control relay in its normal position for completing a stick circuit for said second repeating relay; means controlled by said control relay in its reverse position for completing a stick circuit for said first repeating relay; means controlled by the picking up of said first repeating relay for energizing said first lamp; means controlled by the picking up of said second repeating relay for energizing said second lamp; and means effective to energize said third lamp when and only when said first or said second lamp is energized and the stick circuit of said first or said second repeating relay respectively is completed.

15. In a signaling system; a first, a second and a third indication lamp; a polar control relay connected to a circuit; means controlled over said circuit for actuating the contacts of said control relay to normal or reverse positions; a first repeating relay and a second repeating relay; means controlled by said control relay in its normal positionfor completing a pick-up circuit for said 5 first repeating relay; means controlled by said control relay in its reverse position for completing a pick-up circuit for said second repeating relay; means controlled by said control relay in its normal position for completing a stick circuit for said second repeating relay; means controlled by said control relay and its reverse position for completing a stick circuit for said first repeating relay; means controlled by the picking up of said first repeating relay for energizing said first lamp; means controlled by the picking up of said second repeating relay for energizing said second lamp; means efiective to energize said third lamp when and only when said first or said second lamp is energized and the stick circuit of said first or said second repeating relay respectively is completed; and means controlled by said repeating relays in their dropped away positions for preventing the energization of any of said lamps. V

THOMAS J. JUDGE. 

